CJR Boat Rudders

Name: CJR Boat Rudders
Brand: CJR Propulsion

Custom boat and yacht rudders from CJR Propulsion designed with CFD/FEA for the specific hull; cast NiBral or bronze, bolt-on stock or fabricated steel, flow-aligned twisted option, built to IACS class rules.

Description

CJR Boat Rudders are bespoke rudders designed for the specific hull form using CFD and FEA tools, optimised for manoeuvrability, responsiveness, fuel consumption and speed while reducing noise, vibration and cavitation.

Design

Analysis of propeller inflow and hydrodynamic loading
Rudder stock and blade strength calculations; bearing reaction analysis
Can be built to any classification society rules, including all IACS societies

Configurations

Cast rudders – single-piece casting in aluminium bronze or high-tensile bronze; stocks fully CNC machined
Bolt-on stock – flanged stock and blade with bolt ring, usually recessed in the hull, for easy blade replacement or repair
Fabricated – single plate or streamlined NACA profile, welded in stainless or mild steel, offering weight savings on large vessels; welding by class-coded welders
Flow-aligned twisted rudders – matched to the propeller's rotational flow for lower resistance and higher speed without loss of steering

Materials

Nickel aluminium bronze (NiBral) is the most common choice for its corrosion resistance, mechanical strength and resistance to shock and fatigue; other materials available.

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